In the conventional industrial systems of propagation of aquatic animals, their roes or eggs are separated and special living-spaces are provided for them. In all cases, the gas exchange being necessary for the evolution of the roes or eggs is provided from the water which has to be streamed through the living-space constantly in a great amount.
However, the conventional methods and apparatuses for artificial breeding of the roes or eggs have numerous problems. As it is known, the normal evolution of the roes or eggs necessitates specially treated water which has to be streamed in great amount for providing the intensive gas exchange as required by the roes or eggs. This has its reason in the fact that not only the embryo growing in the roes or eggs has to be fed with oxygen but the carbon dioxide produced by them and the nitrogen resulting from the autolysis of the died embryos have to be removed from the water.
For reducing the water consumption, it has been suggested earlier to regenerate and recycle the water coming out of the living-space of the known solutions. It has been proven, however, that this don't make easier and cheaper the artificial breeding of roes or eggs since, for recycling, clearing and regeneration, at least so many machines, materials and energy are needed as for clearing and treating the newly introduced fresh water. Nevertheless, the conventional solution occupies a relatively big surface area and it can only be erected only in the neighborhood of an adapted water source and energy source.
All these factors mean a considerable hindrance in the way of the breeding of roes or eggs under industrial circumstances. Therefore, the breeding of roes or eggs is not solved until yet in the quality and amount as required in today's agriculture.